Longwall mining machine having advance upper and lower cutting means



Sept. 14, 1965 G. JERRIT 3,206,252

LONGWALL 4MINING MACHINE HAVING ADVANCE UPPER AND LOWER CUTTING MEANS Filed March 28, 1961 5 Sheets-Sheet l El Q o EBQ` Sm' Attorneys,

Sept. 14, 1965 G.JERR1T 3,206,252

LONGWALL .MINING MACHINE HAVING ADVANCE UFPER AND LOWER CUTTING MEANS Filed March 28, 1961 5 Sheets-Sheet 2 Sept. 14, 1965 G. JERRIT 3,206,252

LONGWALL lMININCir MACHINE HAVING ADVANCE UPPER AND LOWER CUTTING MEANS Filed March 28, 1961 3 Sheets-Sheet 5 w r Attorneys.

United States Patent O 3,206,252 LONGWALL MINING MACHINE HAVNG AD- VANCE UPPER AND LOWER CUTTING MEANS George Jerrit, Glasgow, Great Britain, assigner to Mayor & Coulson Limited, Glasgow, Great Britain Filed Mar. 28, 1961, Ser. No. 98,911 Claims priority, application Great Britain, Mar. 29, 1961i, 10,978/60 2 Claims. (Cl. 299-44) This invention relates to a machine for mining coal and other minerals and of the type in which the mineral is obtained by a continuous mining operation from the face of a mineral seam for a substantial height or practically the total height of the seam as measured from floor level to roof level.

The invention is a mining machine of the type stated comprising a body which is traversed along the face of the seam, said body having a head, a mineral-getting assembly on said head comprising a shear-cutting means which works in a substantially vertical plane in advance of the head and a wedge shaped projection adjacent to the head presenting an active surface which slopes outwards and rearwards from said vertical plane, lower and upper means on the body for cutting inwards in approximately horizontal planes into the seam substantially laterally beyond the active transverse cutting plane of the shearcutting means and in advance of the next transverse cutting plane which will become deilned during the return traversing movement of the machine in the opposite direction across the seam being mined. Gearing is provided for the simultaneous operation of the upper and lower cutting means along with the yshear-cutting means. The construction of the machine is such that, in the rst traverse along the face, the lower and upper cutting means can both be utilised to cut out kerfs in the seam. In the next and each subsequent traverse, the shear-cutting plane which will become defined during the return mineral already separated from iloor and roof by the lower and upper cutting means, the thin vertical leading edge portion of the wedge follows the shear-cutting means into cut formed thereby and bursts out the entire buttock and the lower and upper cutting means cut out deeper keris laterally of the machine and beyond the plane in which the shear-cutting means will next operate. Therefore, it will be apparent that a substantial proportion of the mineral will be in large blocks, which is usually advantageous in the case of coal.

An example of the machine designed for mining coal will now be described with reference to the accompanying drawings, which are partly diagrammatic and in which:

FIG. l is a side view of the machine, parts thereof being shown in section, and

ICC

rides upon the mine floor. The machine is hauled in one or the other direction by a haulage rope 12 secured to the appropriate one of a pair of hooklike ixtures 13 on the respective bases of heads 8 and 9. There are mainly tive casings in said group, namely a central casing 14 incorporating a reversible electric motor, two gear casings 15 and 16 at opposite ends of the motor, an upper-level gear casing 17 on the casing 15 and a lower-level gear casing 18 on the casing 16.

The body supports an upper cutter disc 20 which is rotated about a vertical axis by motor-driven gearing Within the body. As shown, the disc 20 is lcarried Vby the upper-level gear casing 17, being secured to a shaft 21 journalled at the end of this casing. The drive from the motor 14 is through a train of gearwheels 22 to 25 in the casing 15 driving a vertical shaft 26 journalled therein and a train of gearwheels 27 to 30 extending in the `casing 17 between the shafts 26 and 21. The disc 2l! would be litted with a circular series of pick-boxes around its periphery and coal-cutting picks would be secured in these boxes to cut in a circular path indicated by the dot-dash line 31 in FIG. 1. The disc is of a substantial diametral size so that its picks cut into the seam to a depth well beyond the inner side of the body into the seam of coal which is being mined.

The disc 20 is supported by a two-part collar 32 which can be detached in order that the disc can be lowered several inches clear of the mine roof.

The body also -supports a lower cutter which in the example is an endless motor-driven cutter chain (not shown) supported and guided by a horizontal jib (FlG. 3) extending from underneath the gear casing 1S and aligned with a driving sprocket wheel 41 which is secured to a shaft 42 journalled at the end of said casing. The drive from the motor 14 is through a train of gearwheels 43 to 46 in the casing 16 driving a vertical shaft 47 journalled therein and a train of gearwheels 48 to 5l) in the casing 18 extending between the shafts 47 and 42. The cutter chain would as is usual incorporate a series of inter-linked pick boxes fitted with coal-cutting picks cutting in a path indicated by the dot-dash line 51.

Each head S, 9 of the machine has a coal-getting assembly including shear-cutting means comprising a cutter-chain jib of the kind known as a shear jib; this is a jib which is set to extend horizontally forwards to support and guide an endless cutter chain which cuts in a vertical plane. The paths in which the shear-cutter chains work are indicated by the dot-dash lines 61. Each jib is of a known construction including toggle-like e end frame members 6?. and upper and lower frame mem- FIG. 2 is a `corresponding plan view with parts shown l in section.

FlG. 3 is a transverse view partly in section approximately on the line 3 3 of FIG. 1.

FIG. 4 is a plan view of a device for gathering small coal on the mine oor and conveying it sidewise from the machine.

FIG. .5 is a perspective view of a wedge-like projection at one end of a ramp structure.

Referring to the drawings, the machine shown is double-ended, being devised to work in both directions along a longwall coal face and to cut a new face A in a seam B which is being mined. The body has an inner side which confronts the face A of the seam B and an outer side which is remote from the face A. The body is formed by a group of inter-connected casings extending between two heads 8 and 9, one at each end of the machine and each head having a base 10 which bers 63, 64 the former of which has a pivotal anchorage 65. The construction is such that in whichever jib is leading the members 62 automatically straighten themselves, thereby extending the jib upwards and rendering its cutter chain active. On the other hand, the members 62 of the trailing jib automaticaily fold themselves, so that the jib collapses and its cutter chain becomes idle. Each jib is located with its vertical working plane approximately in line with the inner side limit of the body. Each cutter chain is driven from the associated vertical shaft 26 or 47 by an inter-meshing pair of bevel gearwheels 66, 67 and a cross-shaft 68 to which the gearwheel 67 and the chain-driving sprocket wheel 69 are secured. The gearwheels 2S, 66 are integrally combined, and so are the gearwheels 46, 66.

The guideway formed by each jib and its sprocket wheel 69 may be extensive enough, when the members 62 are straightened, for the cutter-chain to reach from licor level to nearly roof level.

The coal-getting apparatus operatively associated with each of the heads 8 and 9 comprises a wedging projection 7i) (FIG. 5). The two wedging projections 70 are incorporated in and constitute wedge portions of an elongated ramp structure '71 extending from end to end of the body of the machine along the outer side thereof which is remote from the face A of the seam B which is beingcut. Each of the wedging projections or wedge portions 70 of the ramp structure 71 is located within the circuit 61 of one of the shear-cutter chains. The wedge portions 7@ of the ramp structure 71 taper oppositely to provide wedging action as the machine traverses the coal face A in either direction, each wedging projection 70 being operative for only one of the two directions of travel of the machine.

Each of the wedging projections 7G has an eiective coal-bursting surface 70A, FIG. 5, which curves outwards and rearwards from 4a thin leading vertical edge 79B to the upper face 70C :of the ramp structure 71. The surface 70A extends to lloor level, where it is met by a ramp formed by scooplike surface 70D which curves upwards, rearwards and outwards, terminating in an upwardly and outwardly inclined surface 79E that reaches its summit at the upper horizontal face 76C at the top of the ramp structure 71, which leads outwards to an -outer vertical face 71A extending continuously from end to end lof the ramp structure 71.

Underneath the heads 8 and 9 the machine is equipped with a so-called gu-mmer, namely a device which lgathers the iue coal, or gummin-gs, that fall .upon the Vrmine iloor in the progress .of the mach-ine .and which conveys them for disposal beyond the outer side of the pathsof the machine alongside the newly cut face A. lIn the example, each gathering device comprises a gathering arm S0, FIGS, 1 and 4, which is pivota'lly mounted between its ends on a crank pin 81 dependent from a crank 82 secured to the foot of the associated vertical shaft 26 `or 47. The .arm 80 is pivotally connected by a pin `83: at one end to the end of a swinging link 84 which has a pivotal anchorage at 85 in the associated base 10. In the rotation of the shaft 26 or 47, whichever is in oper-ation, the arm 80 circulates with the crank pin 811 and performs `an outward gathering and pushing motion about the swinging axis provided by the pin 83 on the free end of a swinging link `84.. Link 84 is pivoted at 85 to the machine frame. 'Ihe locus of the tip of the gathering .arm 8f) is represented by the dot-dash line 86 in `FIG. 4. Both .gathering devices work near the inner side of a further ramp 71B extending by a face formed throughout the middle portion of the ramp structure 71, this tace sloping upwards and outwards, as shown in FIGS. 3 and 5.

The machine works in association with a tace conveyor the frame of which is indicated by 90 in FIG. 3. This is a scraper type conveyor pro-vided to receive the coal cut from the face and to deliver the coal to some point appropriate for conveyance of the coal from the mine workings.

Provision is made for disengaging the drive from the electric motor 14 to the gearing between it and the mecha- -nism carried by each of the two heads 8 and 9. In the example, in order that disengagement can be effected, each of the geanwheels 22 and 43 is slidably mounted on opposite ends of the mot-or shaft, of which both ends are splined as indicated by 91, :and each of said gearwheels has a collar 92 by means of which the gearwheel can be slid into or out of mesh ywith the gearwheel `23 or 44 so as to enga-ge or disengage the gearing `of the associated head 8 or 9 with or from the electric motor.

Assume that the machine is to be set for haulage by the rope 12 towards the left of iFIGS. l and 2; that is, with the head 8 leading. Assume also that the coal seam has not previously been worked by this machine and that the face A lof the seam is simply vertically flat. At the ends of the face there are provided two stables, namely spaces (not shown cut into the coal seam B large enough to accommodate the machine. In the iirst instance, the

machine is required to cut int-o the seam a kerf at lloor level .and a kerf at roof level. Accordingly, the machine is positioned .with its shear jibs 62-64 in alignment with the existing coal face, lso that neither of these jibs will cut into the face. The electric motor 14 is now started and the haulage gear is set in operation. In the advance of the machine from right to left of the workings, the upper and lower cutting means carried by the disc 20 and the jib 40 will cut high and low level kerfs in the seam B, as indicated by C and D in FIG. 3. The rear gathering device, driven :by the gearing of the trailing head 9, will gather the coal cut-out and force it .over the ramp 711B to the conveyor 90.

When the machine reaches the left-hand end of the seam, it is again positioned in the appropriate stable and arranged this time to make a full working travel to the right-hand end. Accordingly, the machine is set with the shear jib of the head 9 ready to extend :automatically land cut at full depth into the seam B. The conveyor is shifted laterally to extend alongside the existing coal face behind which the machine is now to cut. The electric motor is started in the opposite direction.

vIn the advance of the machine the coal-cutting picks `of the upper disc 29 and the lower jib 40 cut deeply into the seam B, FIG. 3, forming therein extensions of the kerfs C and D at roof and floor level; the cutter-chain of the shear jib 61-64 cuts ina vertical plane behind the original -coal face, forming the new face A and thus back-cutting a 'butt-eck of coal already severed top and bottom from the roof vand floor by the initial kerfs C and D formed in the previous preparatory travel of the machine. The one of the two wedging project-ions 70 which .is located within the particular `circuit 61 of the shearcutter chain follows the :chain into the cut formed thereby. The surface 70A of the projection 70 engages behind the .buttock and forces it oil from the seam in mainly large blocks. lMuch of this coal will fall clear of the path of the machine upon the face conveyor 90 between which and the new face A the machine works. Coal falling -in fthe path of the wedge shaped projection 70 will be scooped up by the scooplike ramp surface 70D and will be forced to ride -up and over the surface 70E, whence this coal will fall upon the face conveyor. Pine coa-l cut down by the coal-cuttingy picks is gathered `and shifted transversely clear of the body 'by the gathering arm 80 `of the now trailing head 8, which arm follows the upper and lower cutting means 20 and 49; and this gathered lcoal is forced to pass over the further ramp 71B to the conveyor 9i).

In the operation of the machine, the upper and lower cutting means are driven in directions such that their coalcutting picks ycut outwards from the seam towards the face A so that the picks will .act to pull the machine body towards the new coal face A.

When the machine reaches the end of its travel, it is re-positioned in the stable there and set to work in the opposite direction, namely from right to left. Thereafter, the electr-ic motor is started, again in the Vopposite direction.

Any of various modication-s may be made. =For instance as both the upper and lower cutting means one may use short jibs (such as the jib 40) with cutter chains or one may instead use rotary cutter-discs (such as the disc 20); and one might use a lar-ge vertical cutter disc instead :of each leading shear jib and cutter chain. Any of various means can be used for the haulage of the machine. For ins-tance, the machine body may support a haulage gear, including a haulage drum on which is rwound a haulage cable that is anchored at one end of the mine workings. Alternatively, the bodyy may have a rotatable pulley which is wrapped by an endless travelling haulage cable extending from end to end of the mine workings .and which can be locked against rotation when haulage yby the cable has to take place; or the body may have simply a clutch to engage such a travelling haulage cable.

I claim:

11. A mining machine of Ithe class described, comprising: an elongated bi-directionally longitudinally movable body having an inner side which confronts and is traversed along the face of the seam -being mined and an outer side remote from said face; a head at each end of said Ibody; shear-cutting means connected to each head, each shear-cutting means operating in a substantially vertical plane in advance of the head to which it is connected; lower and upper cutting means located be- Iltween said heads and projecting `substantially horizontally at approximately mine-oor and mine-roof levels respectively laterally from said inner side of said body into said face Ibeyond the operational plane of said shearcutting means for cutting into said seam to a substantially ygreater depth than said shear-cutting means; reversible power operated means including gearing for driving said shear-cutting means and said lower `and up'per cutting means simultaneously; an elongated horizontal ramp structure extending at lloor level along the outer side of said body; two oppositely tapered longitudinally spaced wedge members carried by said body, each wedge member includ-ing Va -thin vertical leading edge portion which follows one `of said shear-cutting means into the cut formed thereby, whereby the wedge member bursts out buttocks of mineral previously severed lby the combined action of said lower, upper and shear-cutting means; two longitudinally spaced ramps included in said ramp struc-ture, each of said ramps leading upwardly and outwardly from the outer side of the bottom of one of said wedge members to the top of said ramp structure; .a central ramp included in said ramp structure Iand extending upwardly and outwardly intermediate said two ramps to the top of said ramp structure; and gathering means voperated by said power operated means and disposed inwardly of said central ramp, said gathering means being positioned to feed tine mineral .accumulating lat tloor level -to the lower portion of said central ramp.

2. A machine as claimed in claim 1, in which eac-l1 shear-cutting means comprises a vertical frame jib which supports .and guides an endless cutter chain; wherein said lower cutting means comprises a horizontal jib supporting and guiding an endless cutting chain and in which said upper cutting means comprises a vertical-axis rotary cut-ter.

References Cited by the Examiner UNITED STATES PATENTS 1,741,714 12/29 Hughes.

FOREIGN PATENTS 827,048 1/ 5 2 Germany. 686,9119 2/5'3 Great Britain. 707,898 4/54 Great Britain. 717,607 10/ 54 Great Britain.

30 BENJAMIN HERSH, Primary Examiner. 

1. A MINING MACHINE OF THE CLASS DESCRIBED, COMPRISING: AN ELONGATED BI-DIRECTIONALLY LONGITUDINALLY MOVABLE BODY HAVING AN INNER SIDE WHICH CONFRONTS AND IS TRAVERSED ALONG THE FACE OF THE SEAM BEING MINED AND AN OUTER SIDE REMOTE FROM SAID FACE; A HEAD AT EACH END OF SAID BODY; SHEAR-CUTTING MEANS CONNECTED TO EACH HEAD, EACH SHEAR-CUTTING MEANS OPERATING IN A SUBSTANTIALLY VERTICAL PLANE IN ADVANCE OF THE HEAD TO WHICH IT IS COINNECTED; LOWER AND UPPER CUTTING MEANS LOCATED BETWEEN SAID HEADS AND PROJECTING SUBSTANTIALLY HORIZONTALLY AT APPROXIMATELY MINE-FLOOR AND MINE-ROOF LEVELS RESPECTIVELY LATERALLY FROM SAID INNER SIDE OF SAID BODY INTO SAID FACE BEYOND THE OPERATIONAL PLANE OF SAID SHEARCUTTING MEANS FOR CUTTING NTO SAID SEAM TO A SUBSTANTIALLY GREATER DEPTH THAN SAID SHEAT-CUTTING MEANS; REVERSIBLE POWER OPERATED MEANS INCLUDING GEARING FOR DRIVING SAID SHEAR-CUTTING MEANS AND SAID LOWER AND UPPER CUTTING MEANS SIMULTANEOUSLY; AN ELONGATED HORIZONTAL RAMP STRUCTURE EXTENDING AT FLOOR LEVEL ALONG THE OUTER SIDE OF SAID BODY; TWO OPPOSITELY TAPERED LONGITUDINALLY SPACED WEDGE MEMBERS CARRIED BY SAID BODY, EACH WEDGE MEMBER INCLUDING A THIN VERTICAL LEADING EDGE PORTION WHICH FOLLOWS ONE OF SAID SHEAR-CUTTING MEANS INTO THE CUT FORMED THEREBY, WHEREBY THE WEDGE MEMBER BURSTS OUT BUTTOCKS OF MINERAL PREVIOUSLY SEVERED BY THE COMBINED ACTION OF SAID LOWER, UPPER AND SHEAR-CUTTING MEANS; TWO LONGITUDINALLY SPACED RAMPS INCLUDED IN SAID RAMP STRUCTURE, EACH OF SAID RAMPS LEAIDNG UPWARDLY AND OUTWARDLY FROM THE OUTER SIDE OF THE BOTTOM OF ONE OF SAID WEDGE MEMBERS TO THE TOP OF SAID RAMP STRUCTURE; A CENTRAL RAMP INCLUDED IN SAID RAMP STRUCTURE AND EXTENDING UPWARDLY AND OUTWARDLY INTERMEDIATE SAID TWO RAMPS TO THE TOP OF SAID RAMP STRUCTURE; AND GATHERING MEANS OPERATED BY SAID POWER OPERATED MEANS AND DISPOSED INWARDLY OF SAID CENTRAL RAMP, SAID GATHERING MEANS BEING POSITIONED TO FEED FINE MINERAL ACCUMULATING AT FLOOR LEVEL TO THE LOWER PORTION OF SAID CENTRAL RAMP. 